I complained to the management about late night noise before, and when I came again after another party, they denied I ever came before to complain. Then I asked them to sign a paper that I prepared myself that only acknowledges the fact that I came that second time and notified about the problem, and obviously they wouldn't sign.
How am I supposed to prove I ever came at all, then? If they don't want to sign my paper - fine, but aren't they supposed to have an official book of complaints where any tenant can leave a note? Is there some sort of a regulation that obliges them to have a book/online form/etc. that anyone can go back to and see all complaints there? So far, there is just no way of proving I left any complaints at all (there are other issues as well).